It is known in the art to provide a portable dock in the form of a dock structure carried on a vehicle-towed trailer so that the dock can be used at different locations by towing the trailer to the desired site. U.S. Pat. No. 4,092,755 of Hughes and U.S. Pat. No. 4,505,619 of Sargent teach such dock and trailer combinations. However, the trailer of each of these references is intended not only to support and transport the dock, but also to transport a boat upon the same trailer unit. As a result, the trailer and dock combinations of these two references each include features that, while useful in their intended context of towing a boat behind a towing vehicle and subsequently launching the boat at a site where the dock is to be temporarily installed, may be less than desirable in other contexts, such as using the dock for a canoe or kayak launch where a dedicated boat trailer is typically not required or using the dock simply for swimming or fishing purposes.
For example, the dock trailer of Hughes appears to be intended to sink below the surface of the water when backed into the body of water so that the boat can then be launched off the bunks carried atop the deck of the dock structure. In one embodiment, the dock therefore relies on vertical anchor bars or stilts mounted to rear corners of the trailer dock to subsequently carry the weight of the deck above the surface of the water after launching of the boat. The wheels of the trailer disrupt the sea bed floor during entry of the trailer into the water, and the anchor bars then subsequently disrupt additional areas of the sea bed. It would be desirable to reduce this disruption for minimal ecological impact.
In another embodiment, the sinking and floating of the dock needed for loading of the boat and use of the dock, respectively, is controlled through filling and draining of floatation tubes with water, as they float when filled with air but sink when filled with water. This requires removal and installation of multiple plugs on multiple flotation tubes and draining water from the tubes for replacement with air can only be achieved by removal of the water filled tubes from the body of water. Furthermore, lowering of the deck beneath the surface of the water for launching of the boat wets the deck surface, making it potentially slippery and hazardous for users. It would be desirable to provide a trailer carried dock that is easily preparable for floating and/or is deployable without submersion of the deck surface in the body of water.
Sargent's trailer and dock combination features only very narrow walkways so as not to interfere with the significant trailer area required for carrying the boat on the trailer. Walkways are pivotally carried at a rear end of the trailer to fold outward therefrom for use after launching of the boat. A winch is used in conjunctions with a cable assembly to pull the walkways back into their storage position after use. The cable run above the walkways, and thus are either installed only when needed and subsequently removed or carefully navigated around when using the walkways. In a dock structure pivotally mounted on a trailer frame, it would be desirable to be able to control the dock's pivotal motion without cables interfering with safe use of the dock or limiting the useful area thereof.
Also, neither reference provides for a person's easy transition from the truck bed or cargo hold of the towing vehicle to the dock carried on the trailer, as one would either need to step down from the towing vehicle to the ground then walk to and step back up onto the dock or carefully step down onto and balance upon a narrow trailer frame member at the towing end thereof to walk to the dock carrying rear portion of the trailer, thereby risking a fall and possible resulting injury. It would be desirable to provide a portable dock system that provides a transition walkway from the towing vehicle to the dock for direct and safe walking from the two vehicle to the dock.
In view of the forgoing shortcomings of the prior art, there is room for improvement in portable dock systems.